Gun bolt

ABSTRACT

A gun bolt system is provided which completely fills the extractor groove of the case during firing of the round of ammunition.

United States Patent n 1 on 3,880,045

Clark Apr. 29, 1975 l GUN BOLT 156] References Cited [75} Inventor:Burton Parker Clark. Saint George, UNITED STATES PATENTS 317mm 3/1965Rocha .w 89/9 n 3.3ll3 744 2/l967 [.nnizzuni l. 89/) T i Compan)3.548.709 mum Princc U sum Burlington. Vt,

[22] Filed: Apr. 9. 1974 Primary Erumz'nvr-Benjamin A. Borchcll:iAAiXItIH! fimmincr-C. T. Jordan 2 5 55 Appl 4 9 7 :iH'H'Ht). Agi'm. orl-zrm-BznIm L. lxuch Related U.S. Application Data [62] Division of SerNo. 148L952. Jul 23. 1973. I57] ABSTRACT A gun holt system is providedwhich completely fills I52] 89/9 the extractor groove of the case duringfiring of the lm. Cl. F-lld 7/00 round of nmmuniliun. [58] Field ofSearch 43/m 89/9 4 Claims, 7 Drawing Figures {53 i In 32 J lO IPATENTEDAPRZSIQIS SHEEI 10F 2 w e u 4 PATENTED 2 3.880.045

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GUN BOLT This is a division of application Ser. No. 381951. filed7/23/73.

BACKGROUND OF THE INVENTION I. Field of the Invention This inventionrelates to gun bolts for use with rounds of ammunition having a casewith an extractor groove; and is especially adapted to such cases madeof relatively weak material such as plastic.

2. Description of the Prior Art Modern, conventional. cased ammunitionhas a metal case of the configuration shown. for example. in U.S. Pat.No. 3.498.221 issued to Hilton et al. on Mar. 3. I970. Various proposalshave been made to make such cases out ofplastic. but apparently the onlysignificant use of plastic has been in shot gun shell cases asdiscussed. for example. in U.S. Pat. No. 3.678.858 issued to Herter etal. on July 25. I972. This maybe due to the fact that when plastic issubstituted for metal in a case having an extractor groove. the plasticis not strong enough to alone withstand the internal pressures of theexplosion. and requires support over all ofits external surfaces topreclude rupture.

BRIEF SUMMARY OF THE INVENTION It is an object of this invention toprovide a gun bolt and chamber system which fully supports a case havingan extractor groove.

A feature of this invention is the provision of a gun bolt system whichcompletely fills the extractor groove of the case during firing of theround of ammunition.

BRIEF DESCRIPTION OF THE DRAWING These and other objects. features andadvantages of this invention will be apparent from the followingspecification thereof taken in conjunction with the accompanying drawingin which:

FIG. I is a view in longitudinal cross-section of a gun bolt and chambersystem embodying this invention, taken along the plane II of FIG. 2,showing a round being rammed with the bolt unlocked;

FIG. 2 is a view in transverse cross-section of the system of FIG. 1taken along the plane Illl of FIG. 1;

FIG. 3 is a view in longitudinal cross-section of the system of FIG. 1,taken along the plane IIIIII of FIG. 4, showing the round being rammedwith the bolt un locked and the case extractor groove filled;

FIG. 4 is a view in transverse cross-section of the system of FIG. Itaken along the plane lV-IV of FIG. 3;

FIG. 5 is a view in longitudinal cross-section of the system of FIG. 1.similar to FIG. 3, showing the bolt and round fully chambered;

FIG. 6 is a view in longitudinal cross-section of the system of FIG. 1,taken along the plane VIVI of FIG. 7, showing the bolt locked; and

FIG. 7 is a view in transverse cross-section of the system of FIG. 1,taken along the plane VIIVII of FIG. 6.

THE PREFERRED EMBODIMENT The embodiment of this invention herein shownand described is as incorporated in the gun having a plurality ofbarrels and respective bolts shown in U.S. Pat. No. 3,722,356 issued toD. P. Tassie et al on Mar. 27. I973; and in the bolt locking systemshown in U.S. Pat.

Ill

No. 3.690.2l5 issued to B. P. Clark et al. on Sept. l1. I972; to whichreference should be made for a more complete disclosure of the gun.Alternatively. this invention may be incorporated in an otherwiseconventional Gatling type gun of the type shown in US. Pat. No.3.380.343 issued to R.E. Chiabrandy on Apr. 30. 1968.

A bolt assembly 10 including a bolt body I2, a bolt face l4, anextractor lug l6. and a cam follower I8 is disposed for reciprocation ina groove 20 in a receiver 22. The groove is aligned with a chamber 24which is here shown as part of the receiver but which mightconventionally be formed as part of the barrel. not shown which is fixedinto the receiver. The receiver is disposed in a housing 26 having aquasi-elliptical cyclindrical cam slot 30. There is relative rotationbetween the receiver and the housing.

Two longitudinal tracks 32 are fixed, as by machine screws. not shown.to the receiver and overlie the groove 20 and extend into two respectivelongitudinal slots 34 in the bolt body to provide longitudinal guidancefor the bolt. The bolt cam follower l8 rides in the housing cam slot 30and serves to reciprocate the bolt between an aft loading and ejectionposition and a forward locking and firing position.

An irregular depth transverse slot 36 is formed into and about theperiphery of the bolt body. A substantially U-shaped lock segment 38rides in the bolt annular slot. The slot may have two opposed flatsurfaces 40. an inner arcuate surface 44. and an outer arcuate surface46. The lock segment has two opposed flat surfaces 48. an inwardlyfacing arcuate surface 50. and two opposed outwardly opening cut-outs 52to accommodate the tracks 32. The extractor lug I6 is a slightly lessthan semi-annular web encircling and extending from the lower halfof theface 14 of the bolt and having two shoulders 53 parallel to andimmediately below the level of the slots 34. An arcuate surface 54 ofreduced radius extends around the upper part of the bolt from andbetween the shoulders 53.

A cross-slide 56 is disposed in a transverse slot 58 in the receiver andis bifurcated into two legs 60, each terminating into an inwardlydirected foot 62. and encompassing an arcuate surface 64. Thecross-slide has a cam follower 66 which rides in a transverse cam slot68 in the housing, and is adapted to pass into the slot 36 and tostraddle the bolt body.

A U-shaped extractor groove filler segment 70 is disposed under thecross-slide 56. The segment has an exterior arcuate surface 72 whichmates with the surface 64, and interior aft arcuate surface 74 whichmates with the forward upper arcuate surface 54 of the bolt, and aninterior forward arcuate surface 76 which mates with the remainder ofthe extractor groove of the case not occupied by the extractor lug 16.

A self aligning, longitudinally effective catch between the bolt and thefiller segment is provided by a projecting ball 78 fixed into thesurface 54 of the bolt and a socket 80 formed into the surface 74 of thesegment. The distal ends of the filler segment are notched at 82 toreceive the ends of the feet 62 of the cross-slide 62, so that, incombination with the extractor lug 16, a full 360 of annulus will fillthe extractor groove of the case.

In operation, the round is handed to the bolt when the bolt is in itsmaximum aft position with the extractor lug l6 entering the extractorgroove of the case of the round. The cam slot 30 brings the bolt forwardalong the guide tracks 32 together with the locking segmeat 38 throughthe unlocked position shown in FIGS. 1 and 2. The cam follower 66 of thecross-slide 56 is in the outermost dwell of the cam slot 68 and thetiller segment 72 is in its aft position transversely aligned with theraised cross-slide S6. and nestled against a shoulder 84 in the housing.The bolt continues forward through the intermediate position shown inFIGS. 3 and 4. The cam follower 66 pushes the cross'slide down togetherwith the filler segments so that the filler segment rides off theshoulder 84 and into the extractor groove of the case. The ball andsocket catch also interlocks. The bolt continues forward to fullychamber the round as shown in FIG. 5. The extractor groove. and also theball and socket catch have carried the filler segment forward of thecross-slide 56 into a recess 86 in the receiver. and the cam follower 66has reached the end of the middle dwell. The cam follower 66 now pushesthe cross-slide 56 down in part into the slot 36 in the bolt, while thecross-slide S6 pushes the locking segment down in part into the slot 58in the receiver thus providing 360 of lock around the bolt. Meanwhilethe ex tractor lug l6 and the filler segment provide 360 of support inand around the extractor groove of the case.

the lug being supported by the wall of the groove 20, and the segmentbeing supported by the wall of the recess 86. After the round has beenfired, the cam follower rides up into the middle dwell. raising thecrossslide to the position shown in FIG. 5. lining up its feet 62 withthe notches 52. As the cam track 30 traverses the bolt aftthe extractorlug pulls the case aft, and the case pushes the filler segment aft tothe position shown in FIG. 3. If a case is absent. then the ball andsocket catch serves to bring the filler segment aft. After the camfollower 66 rides into the outer dwell. raising the cross-slide and thetiller segment to the position shown in FIG. 1. the bolt rides out fromunder the cross-slide to eject the fired case.

What is claimed is:

l. A gun. for firing rounds of ammunition, each round having aperipheral extractor groove. said gun comprising:

a receiver having a plurality of chambers, each having a respectiveinterior wall;

a like plurality of bolts, each longitudinally slidable in said receiverand having a respective extractor lug for disposition within an initial.angularly defined. portion of the extractor groove of a round;

a like plurality of filler segments. each for disposition within theremainder. angularly defined, portion of the extractor groove of theround; and

transport means for initially disposing each of said filler segmentswithin the remainder groove of the respective extractor grooves and forsubsequently disposing both a respective said filler segment and arespective said extractor lug within a respective said chamber intransverse abutment with the respective said interior wall whereby eachextractor groove is substantially filled and supported over its full 360of angular extent.

2. A gun according to claim 1, wherein;

said transport means includes a like plurality of cross-slides, eachrespectively transversely slidable in said receiver for inserting andwithdrawing a respective said filler segment into and out of theextractor groove.

3. A gun according to claim 2 wherein:

said transport means includes a plurality of additional interlock means,each for releasably securing the respective said filler segment to therespective said cross-slide, whereby the respective said cross-slide isadapted to carry said filler segment transversely therewith.

4. A gun according to claim I wherein:

said transport means includes a plurality of interlock means, each forsecuring a respective filler segment to a respective bolt againstrelative longitudinal movement therewith, whereby the respective saidbolt is adapted to carry the respective said filler segmentlongitudinally therewith.

1. A gun, for firing rounds of ammunition, each round having aperipheral extractor groove, said gun comprising: a receiver having aplurality of chambers, each having a respective interior wall; a likeplurality of bolts, each longitudinally slidable in said receiver andhaving a respective extractor lug for disposition within an initial,angularly defined, portion of the extractor groove of a round; a likeplurality of filler segments, each for disposition within the remainder,angularly defined, portion of the extractor groove of the round; andtransport means for initially disposing each of said filler segmentswithin the remainder groove of the respective extractor grooves and forsubsequently disposing both a respective said filler segment and arespective said extractor lug within a respective said chamber intransverse abutment with the respective said interior wall, whereby eachextractor groove is substantially filled and supported over its full360* of angular extent.
 2. A gun according to claim 1, wherein; saidtransport means includes a like plurality of cross-slides, eachrespectively transversely slidable in said receiver for inserting andwithdrawing a respective said filler segment into and out of theextractor groove.
 3. A gun according to claim 2 wherein: said transportmeans includes a plurality of additional interlock means, each forreleasably securing the respective said filler segment to the respectivesaid cross-slide, whereby the respective said cross-slide is adapted tocarry said filler segment transversely therewith.
 4. A gun according toclaim 1 wherein: said transport means includes a plurality of interlockmeans, each for securing a respective filler segment to a respectivebolt against relative longitudinal movement therewith, whereby therespective said bolt is adapted to carry the respective said fillersegment longitudinally therewith.